Content blockers are going to ruin your metrics

If you've been following our newsletter, you know I keep bringing up ad blocking. You might also think it doesn't affect you. I'm here to break your heart—because it does.

If you rely on tools like Google Analytics; marketing automation platforms like Eloqua, Marketo, Pardot, or Hubspot; cloud font hosting services like Typekit; or form validation—these are all services pretty much everyone uses.

The problem is what powers ad blocking, and the controversy around it: content blocking plug-ins. They're a newly supported feature recently released for iOS 9 and coming to Safari on Mac with El Capitan. These have been available as plug-ins for Chrome and Firefox for a while, but haven't gained a huge amount of traction outside of highly technical audiences.

What is content blocking?

Content blocking plug-ins are browser add-ons that can be added to iOS 9 and Safari for Mac; and as extensions for Chrome and Firefox. Content blockers have have an action, block or hide, and a trigger, which could be "this script is from Pardot." Here are three main ways content blocking hurts you: they block scripts, hide layout, and block cookies.

1. Content blockers look for scripts on websites

To get technical for a minute, content blockers use something called a regular expression (regex for short). A regular expression is a set of rules for what to look for, like anything that contains google in the address.

For the most part, but this varies for each blocker, they look where the JavaScript files are hosted as well as common file names for tracking scripts uploaded to your website's server. Some content blockers have lists of 2,000-10,000 specific expressions they evaluate to block everything from ad networks to automation platforms to analytics.

2. Content blockers look for specifc HTML and hide it with CSS

Content blockers can also look for specific bits of HTML. For ads, this fully removes them from the layout to make it look nice. But this can also be used to prevent a pop-over box from displaying a form over top of your blog, or your sticky-footer from sticking. Content blockers look for standard IDs in your HTML content and apply CSS to hide it.

Because content blockers are built on regular expressions they need to look for specific types of HTML. If you're using a common JavaScript library, like jQuery, the IDs are common and therefor easy to block.

3. Content blockers block cookies

Automation platforms rely on cookies, which are temporary files, to store unique user IDs on visitor's computers. These unique IDs get sent to your automation platform to build things like progressive profiling, real-time personalization, or pre-populate form fields.

Some content blockers only block third-party cookies. That means it was made by a script hosted on someone else's server, like Eloqua or Pardot. You can buy upgrades to use first-party cookies but some content blockers also block those.

How do content blockers impact marketers?

You might see a drop in web traffic in Google Analytics.

You might lose all insight into content views in your marketing automation platform

You might lose progressive profiling capabilities

You might not be able to run retargeting campaigns

Your might not be able to accurately run a/b tests or experiments

Your form validation might stop working

If you rely on third-party frameworks some features on your website may not work anymore, like modal boxes and sticky footers

If you use a font hosted on a third-party network, like Typekit, it may not display

What can you do about it?

You have a few options, but at the end of the day you should respect your buyer's decision not to be tracked. But there are a few ways to ensure your analytics work. But first:

Make sure your site looks good with default system fonts like Helvetica (sans serif) and Georgia (serif)

Move important scripts from third-party to first-party.

If you're hosting your automation scripts on a third-party server (i.e. Munchkin, Marketo's tracking bot, is being served *from Marketo*) you'll want to move these to first-party hosted scripts on your own server. You will have added maintenance costs in keeping these scripts updated.

Rename and bundle your scripts

Regular expressions can be fooled. You can rename and bundle your scripts together. This is, however, an arms race.

Don't be a jerk

Your buyer is making a choice to use a content blocker: your interest is in serving them, and you do that best by respecting their choices. Sure, you can throw up text-block that says "You need to turn off content-blocking to see our site." but all that's likely to do is have them buy from another vendor.

Ad blocking and content blocking are here to stay. Your challenge is how to market to your customers and measure your marketing ROI without the complex or invasive tracking systems you had in the past. That's one of the reasons we're building FunnelCake, and we can't wait to share it with you.

Thanks to Francois Mathieu for adding a new item: content blockers will also prevent a/b testing and experiments from running for users with content blockers. This will skew your results.